deliver(SessionID, Data) -> ok | {error, Reason}

This function is only intended to be used from
functions called by the Erl Scheme interface to deliver
parts of the content to the user.

Sends data from a Erl Scheme script back to the client.

Note!

Note that if any HTTP-header fields should be added by the
script they must be in the first call to deliver/2 and the
data in the call must be a string. Calls after the headers
are complete may contain binary data to reduce copying
overhead. Do not assume anything about the data type of
SessionID, the SessionID must be the value given as input to
the esi call back function that you implemented.

The Module must be found in the code path and export
Function with an arity of three. An erlScriptAlias must
also be set up in the configuration file for the Web server.

If the HTTP request is a 'post' request and a body is sent
then content_length will be the length of the posted
data. If 'get' is used query_string will be the data after
? in the url.

ParsedHeader is the HTTP request as a key value tuple
list. The keys in parsed header will be the in lower case.

SessionID is a identifier
the server uses when deliver/2 is called; do not
assume anything about the datatype.

Use this callback function to dynamically generate dynamic web
content. When a part of the page is generated send the
data back to the client through deliver/2. Note
that the first chunk of data sent to the client must at
least contain all HTTP header fields that the response
will generate. If the first chunk does not contain the
End of HTTP header, that is "\r\n\r\n",
the server will
assume that no HTTP header fields will be generated.

This callback format consumes a lot of memory since the
whole response must be generated before it is sent to the
user. This function is deprecated and only kept for backwards
compatibility.
For new development Module:Function/3 should be used.